Abstract: A clamp system has been invented for releasably securing a screen to a vibratory screen apparatus, the clamp system in one aspect having a front plate for abutting a portion of a vibratory screen apparatus, a first link movably connected to the front plate and having a first contact surface, a second link movably connected to the first link and having a second contact surface, a bolt with a first end projecting out beyond the second link and a second end projecting out beyond the front plate, the bolt tightenable in place by an adjusting nut on one end thereof, and the first link and the second link movable so that the first contact surface abuts the second contact surface and the links are then held releasably together.

Abstract: A tong assembly for use in making-up and breaking-out joints of varying diameter. The tong assembly includes a housing, a carrier element, at least one jaw, a link corresponding to each jaw and pivotably connected to the carrier element and to which the corresponding jaw is pivotably connected, a drag device, and a brake. A power device may be connected to the tong assembly to drive the tong and a backup tong may be secured relative to the housing and to the power device of the tong assembly.